Preheating attachment for hardening-furnaces.



H. L. WAISNER.

PREHEATING ATTACHMENT FOR HARDENING FURNACES.

APPLICATION FILED SEPT. 16, 1915.

Patented Dec. 21, 1915. 4

IHIII H uni m m v 7 W W L H COLUMBM PLANOGRAPH c0.. WASHINGTON, n. c.

pr on Hanson L. 'WAISNER, or RocKron-n, rumors.

PREHEATING ATTACI-IIVIENT FOR HARDENING-FURNACES.

Specification of Letters Patent.

Patented Dec. 21, 1915.

Application filed September 16, 1915. Serial No. 51,051.

T 0 all whomz'zf may concern:

Be it known that I, HORACE L. WAISNER,

a citizen of the United States, residing at Rockford, in the county of Winnebago and State of Illinois, have invented certain new and useful Improvements in Preheating At tachments for flardening Furnaces; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to furnaces, andmore particularly to pre-heating attachments for-hardening furnaces, and especially to gas or oil furnaces of this character which are fit-ted with a pot in which lead, barium, cyanid, or other heating medium is placed. I

The object of the invention is to provide a simple and efiicient attachment of this character by means of which the waste heat from the furnace may be utilized for preliminarily heating the articles to be hardened in the furnace to which this attachment is applied, thereby eifecting a considerable saving in fuel.

With this and other objects in view, the invention consists of certain novel features of construction, and the combination and arrangement of parts to be hereinafter more particularly described and claimed.

In the accompanying drawings: Figure 1 represents a front elevation of a furnace equipped with this improved attachment; Fig. 2 is a plan view thereof; Fig. 3 is a side elevation, and Fig. 4 is an enlarged detail sectional View taken on the line 4.4 of Fig. 2.

The furnace F to which this attachment is applied, is of ordinary construction, being shown cylindrical in form and having a lining L of fire clay or other heatretaining lining, and in which a pot P is mounted for containing the article-heating agent.

The attachment constituting this invention comprises an annular plate 1 having its inner edge overlapping the top of the furnace F and on which said attachment is supported (see Fig. 4). This plate 1 projects some distance beyond the side walls of the furnace and has a heat retaining and directing skirt 2 depending from its periphery and tapering toward its lower end, forming a furnace encircling heat-retaining chamber 3 provided with a restricted annular mouth 4 at its lower end (see Fig. 4.) y

The plate 1 is perforated throughout between its skirt and the outer portion of the,

overlapping inner edge thereof as shown at 5 to permit the rising of the heated air therethrough, said air entering the chamber 3 through an opening 6 formed in one side wall of the furnace F near its upper end (see Figs. 1 and 4), and more or less heated air is radiated from the side walls ofthe furnace into said chamber.

The downwardly tapering skirt 3 serves not only to confine the heated air, but also to direct it upward toward the apertures 5 in the plate 1 through which said air passes to the articles mounted on the plateand which are designed to be preliminarily heated by said air, before they are inserted in the pot P which contains the heating or articles before submerging them in the contents of the pot P, a considerable saving in the fuel for heating the pot is effected, as less heat will be absorbed from the heating agent in the pot by the pre-heated articles than if they were submerged when cold.

As shown, a flange 8 rises from the plate 1 near its periphery and is provided at its base on the outer face thereof with a shoulder 9 forming a seat for a guard 10 which is here shown extending around about three quarters of the circumference of the plate 1 to protect the articles placed on the plate 1 and prevent them from .being accidentally displaced. This guard is omitted from the front portion of the furnace to provide for the manipulation of the articles being heated and to permit them to be inserted in the pot P after they have been so heated.

i Vhile the guard 10 is shown made in the form of a separate member secured to the flange 8, it may be cast integral with the plate 1 if desired.

As shown, the skirt 2 is made in two sec tions with the ends thereof overlapping and bolted together as shown in Fig. 1. The plate 1 is also shown formed of two semicircular sections with tongues or apertured lugs'l and 1 arranged one on one end of one section and one on the other end of the other section which underlap the meeting ends of the opposite section and are shown bolted thereto (see Fig. '2).

From the above description it will be obvious that this heating attachment may be applied to any furnace or stove and may be employed for heating any other articles than those above specified.

' and project beyond the side walls, and means for retaining heat supplied from the furnace I to which the device is applied and for di erecting it upward through said perforated plate.

2. A heating attachment for furnaces comprising a perforated plate adapted to be mounted onthe top of a furnace or stove and project beyond the side walls, means' for retaining heat supplied from the furnace to which the device is applied and for directing it upward through said perforated plate, and a vertical protecting guard carried by said'plate;

3. A heating attachment for furnaces comprisinga perforated plate adapted to be mounted on the top of a stove or furnace and project beyond the side walls thereof, and a skirt depending from the periphery of said plate.

- 4.4! heating attachment for furnaces comprising a perforated plate adapted to be mounted on the top of a stove or furnace and project beyond the side walls thereof, and a skirt depending from the periphery witnesses.

eral edge of said plate and tapering toward its lower end. 7 t

6. A heating attachment for'furnaces comprising an annular perforated plate coin-- posed of two semi-circular sections having tongues at one end lapping the end of the adjacent section, means for securing said tongues to the adjacent section, and a skirt dependingfrom theperipheral edge of said plate.

7, The combination with'a furnace having an opening in the sidewall thereof near its upper end, a plate resting on the top of said furnace andprojecting' beyond the side walls thereof, the portion of said plate beyond said side walls being perforated, and a skirt depending from the peripheral edge of said plate and forming a heat retaining and directing member.

In testimony whereof I have hereunto set my hand in presence of two subscribing HORACE L. WAISNER.

Witnesses: I J

J. D. TAYLOR,

T. JoHNsoN'f I Collies of h patent may be obtained for fiveucents each, by addressing the Com i i er f Patent% 7 Washington, D. 0. f V V i 

